Carpets containing synthetic polymer fibers are a popular floor covering for both residential and commercial applications. Such carpets are relatively inexpensive and have a combination of desirable qualities, such as durability, comfort, safety, warmth, and quietness.
Various types of synthetic polymer fibers are used in making carpets. Two popular synthetic polymer fibers utilized in carpets are polyamide fibers, such as nylon 6, and nylon 6/6, and polyester fibers.
The fibers contained in the carpets are severely and permanently stained or soiled when contacted, such as by inadvertent spilling, with certain artificial and natural colorants present in household items, such as tea, coffee beverages made from coffee beans, and soft drink beverages. Many of these colorants are acid dye colorants, which cause the most severe stains. As a result thereof, carpets are sometimes replaced because of unsightly soiling or staining, even though the carpet has not been worn out.
The terms "stain" and "staining" as used herein with reference to synthetic fibers mean discoloration of the fibers caused by a reaction with a chemical substance. Acid dyes are representative of a staining material for nylon fibers.
The term "soils" as used herein refers to both organic and inorganic matter which comes in contact with fibers and adhere thereto. Dirt particles, grease, oils, foods, and cosmetics are representative of materials referred to as soils that work their way onto and into various textile fibers.
The term "fiber" as used herein includes fibers of extreme or indefinite length (i.e. filaments) and fibers of short length (i.e. staple). The term "yarn" as used herein means a continuous strand of fibers.
In an attempt to prevent undesirable staining of fibers and, particularly, fibers contained in carpets, it has been proposed that the fibers be treated with an additive which coats the fiber and makes the fiber resistant to staining. Examples of such additives are condensation products made from aromatic sulfonic acids, and formaldehyde. Although such additives have been somewhat successful in imparting stain resistance, certain problem remain. For instance, many of the additives reduce staining of fibers, but do not totally eliminate it. In addition, traffic on carpet wears off the additives, which leaves the resulting fibers of the carpet with little or no protection against sing.
Colored food beverages, such as colored soft drink beverages, tea beverages, and coffee beverages made from coffee beans, present a serious staining problem to textile fibers. Coffee stains are particularly unsightly because of their dark brown color. Also, coffee stains are notoriously difficult to remove from many synthetic fibers.
Various fluorochemicals have been applied to carpet fibers in order to reduce their water and oil wettability. The fluorochemical reduces the tendency of soils to adhere to the fibers, thereby making the removal of soils from the carpet fibers easier than if the fluorochemicals were omitted, but offers little protection to the carpet fibers from spills containing acid dye colorants unless the colorants are immediately removed from the fibers. In addition, traffic on the carpet wears off the fluorochemicals.
A number of cleaning solutions have been proposed in the past for removing stains and soils from fibers. For instance, volatile solvent dry-cleaning fluids have been proposed, but such fluids are less than satisfactory in removing water-soluble stains or soils. In addition, aqueous compositions containing synthetic detergents have been proposed for removing stains and soils from fibers, but such compositions have not been found to be particularly effective.
One of the problems with these cleaning solutions is that while they may, at times, loosen and/or disperse the soil, they fail to pick up or retain the soil, which results in the soil being redeposited on the fibers. Furthermore, they are not very effective against difficult stains, such as acid and coffee stains. Still further, since acid and coffee stains are believed to bond chemically with the fiber, aqueous detergent compositions are not particularly effective and many times it is difficult to remove all of the detergent from the fiber surface, even when rinsed with large amounts of water or steam. As a result thereof, the carpet fibers become tacky due to a film of detergent. The film attracts and retains soils, which results in a cleaned carpet that will soil more easily after a cleaning than prior thereto.
The present invention provides a cleaning composition suitable for removing stains and staining from soils from synthetic polymer fibers which overcomes, or at least mitigates, many of the above-described problems.